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Effects of earthquake on fresh and hardened concrete
No full textTürkiye’de meydana gelen ve asrın felaketi olarak adlandırılan 6 Şubat Depremleri 11 ilde 50 binden fazla can kaybına ve 40 bin civarında yapının yıkılmasına neden olmuştur. Bu çalışmanın temel amacı, ana depremin yanında ardışık ve artçı depremleri de dikkate alarak, depremin beton dayanımı üzerindeki etkilerini irdelemektir. Diğer taraftan ülkemizde özellikle depremde enkaz haline gelmiş binalardan alınan karotların deneye tabi tutulması sonucu elde edilen dayanım değerleri ile proje betonunda öngörülen beton sınıfının karşılaştırılmasının doğru olup olmadığının ortaya konulması da amaçlanmaktadır. Depremlerin beton dayanımı üzerindeki etkisi; taze ve sertleşmiş beton olarak iki ayrı grup beton üzerinde değerlendirilmiştir. Yapılan çalışmalar sonucunda, taze betonun 3 güne kadar depremden etkilendiği ve dayanımında %15-20 gibi belirli oranlarda düşüşler olduğu ortaya konulmuştur. Depreme maruz kalmış bir yapıdaki beton dayanımının depremden etkilenmesini her durumda geçerli olabilecek şekilde ortaya koyabilen bir çalışmaya yazarlar tarafından rastlanılmamıştır. Önümüzdeki yıllarda depremlerden elde edilen veriler kullanılarak yapay zekâ ortamında belirli deprem etkileri için de olsa dayanım düşüşünü ortaya koyan çalışmaların yapılması olasıdır. Dolayısıyla günümüzde deprem geçirmiş ve enkaz haline gelmiş bir bina için projesindeki beton sınıfı için öngörülen dayanımla, enkazdan alınan karotların dayanımlarını doğrudan karşılaştırmak doğru bir yaklaşım değildir. Zira henüz karot sonuçlarının nasıl değerlendirileceği yönetmelik ve standartlarımızda belli değildir.February 6 earthquakes, which occurred in Turkey and were called the disaster of the century, caused more than 50 thousand deaths and the collapse of around 40 thousand structures in 11 provinces. The main purpose of this study is to examine the effects of consecutive and aftershock earthquakes on concrete strength, considering the main earthquake. It is also aimed to reveal whether the comparison of the strength values obtained by testing the cores taken from buildings that have been destroyed in earthquakes in our country and the concrete class envisaged in the project concrete is correct or not. It was revealed because of experimental studies that fresh concrete is affected by earthquakes for up to 3 days and its strength decreases by 15-20%. In the coming years, it is possible that studies will be conducted using data obtained from earthquakes using artificial intelligence to reveal the decrease in strength, even for certain earthquake effects. Therefore, it is not a correct approach to directly compare the strength of the concrete class foreseen in the project of a building that has been subjected to an earthquake and turned into rubble with the strength of the cores taken from the rubble
Value chain analysis in technical textiles and composite materials sector: A regional case study
No full textThis study has been prepared as the value chain analysis for the Bursa Technical Textile and Composite Materials Cluster. The study aims to identify key actors in the value chain, competencies, and areas to be developed in the cluster ecosystem. The industrial scope of the study covers technical textiles and composite materials together, as, in many ways, Bursa enjoys the presence of sophisticated companies and strong infrastructure to specialize further and be one of the world's leading centres for the industry. Industry-level value chain analysis detailed each value chain process in terms of its main competencies and development areas. The value chain analysis reviewed the parameters of the Diamond Model to form the basis of a strategic vision for the future. Based on the findings, the report has an early-stage action plan for the cluster management team to undertake steps in the very short term, which can go hand in hand with the strategic development stage.European Union (EU)Republic of Turkiye-EuropeAid/140069/IH/SER/TR-TR14C1.1.09-04/001/Servic
Examination of the relationshıp between peer bullying, emotion regulation skills and perceived social support in 7th and 8th grade students: Secondary school students sample
No full textZorbalık hem dünyada hem de ülkemizde birçok insanı doğrudan etkilemekte ve birçok araştırmaya konu olmaktadır. Ergenler arasında yaygın olan akran zorbalığı üzerine yapılan bu çalışmadaki amaç, ortaokul 7. ve 8. sınıfta eğitimine devam eden öğrencilerin akran zorbalığı deneyimlerinin (zorbalık yapma ve zorbalığa maruz kalma) sahip oldukları duygu düzenleme becerileri ve algıladıkları sosyal destek ile ilişkisini incelemektir. Çalışmaya Bursa’nın merkez ilçesindeki bir ortaokulda 2023-2024 eğitim - öğretim yılında öğrenim gören 876 öğrenci (416 kız ve 460 erkek / 431 7. sınıf ve 445 8. sınıf) katılmıştır. Kişisel Bilgi Formu, Akran Zorbalığını Belirleme Ölçeği, Ergenler İçin Duygu Düzenleme Ölçeği (EİDDÖ) ve Algılanan Sosyal Destek Ölçeği (ASDÖ-R) kullanılarak veriler toplanmıştır. Veriler normal dağılıma sahiptir ve bu sebeple analizde parametrik teknikler kullanılmıştır. Sınıf ve cinsiyet açısından zorbalık ve mağduriyetin farklılaşma durumunu ortaya koymak için t testi, anne ve baba eğitim düzeyi açısından farklılaşma durumunu ortaya koymak için tek yönlü varyans analizi yapılmıştır. Zorbalık ve mağduriyetin algılanan sosyal destek ve duygu düzenleme becerileri ile ilişkilerini tespit etmek için ise korelasyon analizi yapılmıştır. Çalışmada akran zorbalığı ve mağduriyetinin cinsiyet ve sınıf düzeyine göre farklılaştığı, anne eğitim düzeyine göre bir farklılaşma bulunmadığı, sadece zorbalığa maruz kalma durumunun baba eğitim düzeyine göre farklılaştığı tespit edilmiştir. Duygu düzenleme yöntemleri ve algılanan sosyal desteğin akran zorbalığı ve mağduriyeti ile ilişkili olduğu bulunmuştur.Bullying directly affects many people both in the world and in our country and is the subject of many studies. The aim of this study on peer bullying, which is common among adolescents, is to examine the relationship between peer bullying experiences (bullying and being bullied) and emotion regulation skills and perceived social support of 7th and 8th grade students. 876 students (416 girls and 460 boys / 431 7th grade and 445 8th grade) studying in a secondary school in central district of Bursa in the 2023-2024 academic year participated in the study. Data were collected using the Personal Information Form, Peer Bullying Scale, Emotion Regulation Scale for Adolescents and Perceived Social Support Scale. The data have a normal distribution and therefore parametric techniques were used in the analysis. A t-test was used to reveal the difference in bullying and victimization in terms of class and gender, and a one-way analysis of variance was used to reveal the difference in terms of mother and father education levels. A correlation analysis was used to determine the relationships between bullying and victimization and perceived social support and emotion regulation skills. In the study, it was determined that peer bullying and victimization differed according to gender and class level, there was no difference according to mother education level, and only victimization differed according to father education level. It was found that emotion regulation methods and perceived social support were related to peer bullying and victimization
Retrospective study of short and long-term results of neoadjuvant therapy, surgical resection, and curative chemoradiation therapy in the treatment of esophageal cancer
No full textDünya çapında her yıl yaklaşık 500.000 hastaya özofagus kanseri tanısı konmaktadır. Kuzey Amerika'da görülme sıklığı son 20 yılda neredeyse iki katına çıkmıştır ve dünya çapında en sık görülen 8. kanserdir. Skuamöz hücreli karsinom (SCC) ve adenokarsinom (AdenoCa), özofagus malign tümörlerinin yüzde 95'inden fazlasını oluşturur. 20. yüzyılın büyük bölümünde SCC hakim oldu. 1960'larda SCC, Amerika Birleşik Devletleri'ndeki özofagus tümörlerinin yüzde 90'ından fazlasını oluşturuyordu ve adenokarsinomlar çok nadir görülüyordu. Bununla birlikte, zamanla özofagus adenokarsinomunun insidansı batı ülkelerinde dramatik bir şekilde artmıştır, öyle ki, adenokarsinom şu anda Amerika Birleşik Devletleri'ndeki tüm özofagus kanserlerinin yüzde 60’ından fazlasını oluşturmaktadır. Bu çalışmada özofagus kanseri tanısıyla tedavi edilen hastalarda uygulanan farklı tedavi yaklaşımlarının kısa ve uzun dönem sonuçlarını karşılaştırmak amaçlanmıştır. Direkt cerrahi uygulanan hastalar, neoadjuvan tedavi sonrası cerrahi uygulananlarla karşılaştırılmış, ayrıca cerrahi yapılan hastalar ile sadece küratif kemoradyoterapi (KRT) uygulanan hastalar sağkalım ve komplikasyonlar açısından analiz edilmiştir. Retrospektif olarak değerlendirilen hasta grupları üçe ayrıldı: Grup 1 - direkt cerrahi, Grup 2 - neoadjuvan tedavi sonrası cerrahi, Grup 3 - cerrahi uygulanmaksızın küratif KRT. Hastaların demografik özellikleri, tümör tipleri, yerleşim yerleri, operasyon teknikleri, kısa dönem morbiditeleri (Clavien-Dindo sınıflamasına göre) ve uzun dönem sağkalım verileri karşılaştırıldı. KaplanMeier sağkalım analizi ve Cox regresyon testleri kullanıldı. Direkt cerrahi uygulanan hastalar ile neoadjuvan tedavi sonrası cerrahi uygulananlar arasında sağkalım açısından anlamlı fark bulunmazken, erken evrelerde direkt cerrahinin sağkalım avantajı sağlayabileceği gözlemlendi. SCC alt grubunda cerrahi ve küratif KRT grupları benzer sağkalım gösterirken, adenokarsinom alt grubunda cerrahi uygulanan hastalarda belirgin sağkalım avantajı saptandı.Clavien-Dindo skoru açısından da komplikasyonlar açısından gruplar arasında belirgin farklılıklar görüldü. Ameliyat edilen hastalarda gelişen komplikasyonların KRT verilen hastalarda gelişen komplikasyonlara göre daha yüksek skorlu olduğu görülmüş olup tüm hastalar göz önüne alındığında da skor arttıkça hem hastalıksız hem de genel sağkalımın azaldığı görülmüştür. Özofagus kanseri tedavisinde uygun hastalarda cerrahi halen temel tedavi seçeneği olmaya devam etmektedir. AdenoCa olgularında cerrahi ile daha iyi sağkalım sağlanırken, SCC hastalarında küratif KRT de etkili bir alternatif olabilir. Neoadjuvan tedavi uygulanan hastalarda kısa dönemde morbidite artışı izlense de, uzun dönem sağkalım sonuçları ile dengelenebilmektedir.Approximately 500,000 new cases of esophageal cancer are diagnosed worldwide each year. In North America, its incidence has nearly doubled over the past 20 years, making it the 8th most common cancer globally. Squamous cell carcinoma and adenocarcinoma account for more than 95% of esophageal malignancies. Throughout much of the 20th century, SCC predominated. In the 1960s, SCC made up more than 90% of esophageal tumors in the United States, with adenocarcinomas being very rare. However, over time, the incidence of esophageal adenocarcinoma has dramatically increased in Western countries, to the point where adenocarcinoma now accounts for more than 60% of all esophageal cancers in the United States. This study aimed to compare the short- and long-term outcomes of different treatment strategies in patients diagnosed with esophageal cancer. Patients who underwent primary surgery were compared with those who received neoadjuvant therapy followed by surgery, and both surgical groups were also compared with patients treated with definitive chemoradiotherapy (CRT) without surgery. Patients were retrospectively categorized into three groups: Group 1 – primary surgery, Group 2 – surgery after neoadjuvant therapy, Group 3 – definitive CRT without surgery. Demographic characteristics, tumor types, localization, surgical techniques, short-term morbidity (based on ClavienDindo classification), and long-term survival were analyzed. Kaplan-Meier survival analysis and Cox regression were applied. No significant survival difference was observed between patients undergoing primary surgery and those treated with neoadjuvant therapy followed by surgery. However, primary surgery may provide a survival benefit in early-stage disease. In the SCC subgroup, survival outcomes were comparable between surgical and CRT groups, while in the AdenoCa subgroup, surgery yielded better survival. Major complications (Clavien-Dindo ≥3) showed significant differences among groups. Surgery remains the mainstay of treatment in eligible patients with esophageal cancer. In adenocancer cases, surgery is associated with improved survival, whereas in SCC patients, definitive CRT can be a viable alternative. Although neoadjuvant therapy increases short-term morbidity, it may be balanced by favorable long-term outcomes
Effects of irrigation level, plant density, and nitrogen doses on sweet corn yield and water productivity
No full textPlant density, nitrogen and irrigation management are three important agricultural inputs that affect plant yield and quality. This study was undertaken to ascertain the impact of varying plant densities, irrigation water levels and nitrogen rates on the yield, some yield components and irrigation water productivity (IWP) of sweet corn (Zea mays L.) cultivated in an open-field environment. To this end, two-year field experiments were carried out using the Challenger F1 corn variety on clay-textured soil in the Bursa province located in the Southern Marmara Region of Turkey. In the first year of the experiment, plant density in the main plots and irrigation levels in split plots were randomized. Accordingly, two plant density levels (57000 and 95000 plants ha-1) and three irrigation levels (100%, 67%, and 33% of crop evapotranspiration (ETc)) were applied. In the second year of the experiment, three irrigation levels in main plots (100%, 80%, and 60% of ETc) and three N fertility ratios (150, 300, and 450 kg ha(-1)) in split plots were assigned. A combination of 95000 plants ha-1 population and 100%ETc irrigation ratio provided maximum fresh ear yield. The irrigation treatment 80%ETc, accompanied by 300 kg N ha-1, and 76000 plants ha-1 population was determined as the optimal management system for maximum yield, yield components, and IWP. To preserve soil and water resources, the optimal management system at maximum yield and IWP should be implemented for sweet corn production in the Marmara region
Classification of breast cancer using ensemble machine learning with apache spark
No full textBreast cancer is one of the most common and serious problem affecting people around the world. Detecting it early and correctly identifying whether a tumor is benign or malignant. In this study, we developed a new model called the Logistic Ensemble Fusion Model to im-prove the accuracy of Breast cancer diagnosis. This model combines the strengths of three different machine learning models, specifically Support Vector Machine, Decision Tree, and Logistic Regression, into a powerful ensemble approach, significantly improving over traditional methods. We used Apache Spark with its Python API to handle large datasets quickly and efficiently. To select the important features for making predictions, we used a method called Recursive Feature Elimination (RFE), with the help of both a Support Vector Machine (SVM-RFE) and Random Forest (RF-RFE). We tested our model by dividing the data into training and testing sets in an 80:20 ratio. The Logistic Ensemble Fusion Model achieved an accuracy of 99.13%, precision of 98.71%, recall of 99.91%, and an F1 score of 99.12%. The en-tire process, which involved running 12 Spark jobs, was completed in 38 seconds. Compared to other models like Random Forest, Gradient Boosting, Factorization Machine, One-vs-Rest, and Multilayer Perceptron. The main innovation of this study is the use of multiple machine learning models in a unified ensemble fusion approach, providing classification performance and demonstrating significant advancement over previous methods. This study underscores the potential of advanced ensemble machine learning techniques and big data technologies in refining breast cancer diagnosis and supporting more effective clinical decision-making
Deep learning and supervised learning techniques for modeling and prediction of strength of ground granulated blast furnace slag based sustainable mortar
No full textThis paper presents an analysis and synthesis of deep learning and supervised learning techniques for predicting the flexural tensile strength and compressive strength of mortars containing ground granulated blast furnace slag (GGBFS). The goal is to save time and reduce the costs associated with experimental testing. Initially, mechanical tests were conducted experimentally, using GGBFS as a partial replacement for cement in the mortar, with replacement levels ranging from 0 wt% to 80 wt% in 1% intervals. The results indicated a nearly linear decrease in flexural tensile strength and a non-linear change in compressive strength with increasing GGBFS content. To address the limitations of traditional experimental methods and improve processes, deep learning and supervised learning approaches were explored and compared. Evaluation metrics such as Root Mean Squared Error (RMSE), Mean Absolute Error (MAE), Mean Squared Error (MSE), and R-squared demonstrated that the deep learning model achieved higher sensitivity and efficiency for both 7-day and 28-day flexural tensile strength, as well as 7-day and 28-day compressive strength. Quantitatively, the deep learning model outperformed traditional models for 28-day flexural tensile strength, with an RMSE of 0.6779, an R-squared value of 0.90, an MSE of 0.4596, and an MAE of 0.6045, and for 28-day compressive strength, with an RMSE of 0.6808, an R-squared value of 0.99, an MSE of 0.4636, and an MAE of 0.4891. These findings suggest that deep learning is a promising method for accurately modeling and predicting the mechanical properties of GGBFS-based mortars, particularly for the 28-day strengths
Coupled thermal-structural analysis of bipolar plates in proton exchange membrane fuel cells (pemfcs)
No full textThis study systematically investigates the influence of heating power and the number of plates on the displacement, temperature, and stress characteristics of bipolar plates in Proton Exchange Membrane (PEM) fuel cells, which play a pivotal role in determining the overall performance and durability of fuel cell stacks. A comprehensive numerical simulation framework, implemented via COMSOL Multiphysics, was employed to evaluate these parameters under varied operating conditions, including heating power levels ranging from 200 W to 300 W and plate quantities spanning from 100 to 200. Boundary conditions encompassed manifold pressures between 2 MPa and 8 MPa, as well as heat transfer coefficients in the gas channels varying from 50 to 70 W/m2K. The simulation outcomes reveal that augmentations in heating power and plate count exert a pronounced effect on the mechanical deformation and thermal profiles of the system. Specifically, displacement values ranged from 2.38 mu m to 2.92 mu m, with the maximum displacement observed at 300 W heating power combined with 150 plates, and the minimum at 200 W with 200 plates. Temperature measurements varied between 89.1 degrees C and 103 degrees C, exhibiting a peak at the highest heating power and intermediate plate count, and a minimum at the lowest heating power with the highest plate count. Correspondingly, stress values spanned from 6.12 MPa to 10.7 MPa, following a similar distribution pattern. These findings underscore the critical interdependence of heating power and plate quantity on the structural integrity and thermal management of PEM fuel cell bipolar plates. The results advocate for meticulous optimization of these parameters to enhance mechanical stability, improve thermal dissipation, and ensure prolonged durability of fuel cell stacks under practical operational scenarios. The insights derived from this study provide valuable guidance for the design and operational optimization of PEM fuel cell systems aimed at maximizing reliability and performance
Quadratic interpolation optimization-based 2dof-pid controller design for highly nonlinear continuous stirred-tank heater process
No full textTemperature control in continuous stirred tank heater (CSTH) systems is essential for ensuring energy efficiency, safety, and product quality in industrial processes. However, the nonlinear dynamics and external disturbances make conventional proportional-integral-derivative (PID) control inadequate for reliable operation. This study presents a novel two-degrees-of-freedom PID (2DoF-PID) controller optimized using the quadratic interpolation optimization (QIO) algorithm to enhance CSTH temperature regulation. The QIO-based approach allows independent tuning for setpoint tracking and disturbance rejection, overcoming the limitations of classical PID controllers. Extensive nonlinear time-domain simulations, reference tracking, and disturbance rejection tests demonstrate the superior performance of the proposed controller in terms of reduced overshoot, faster settling time, and minimal steady-state error. Furthermore, comparative evaluations with traditional tuning methods (Murrill and Rovira) and several state-of-the-art metaheuristic optimizers (DE, PSO, FLA, MGO) validate the effectiveness and robustness of the QIO-optimized strategy. This work introduces a pioneering application of the QIO algorithm in industrial temperature control, offering a scalable and cost-efficient solution for complex nonlinear systems